anatomy cumulative

Sagittal plane

Sagittal plane

divides the body into right and left

Para-sagittal plane

sagittal plane not at the midline

Medial

towards the midline

Lateral

away from the midline

Transverse plane

divides the body in superior and inferior

Superior

above or up

Inferior

below or down

Cranial

towards the head

Caudal

towards the tail

Proximal

close to the origin

Distal

away from the origin

Coronal plane

divides the body in anterior and posterior

Anterior

front

Posterior

back

Ventral

stomach

Dorsal

back

Palmar

face of the palm

Dorsal

back of the hand

Dorsal

top of the foot

Planar

sole or bottom of the foot

Buccal

towards the cheek

Occlusal

top of the teeth

Labial

towards the lips

Mesial

towards the midline of the mouth

Lingual

towards the tongue

Deep

towards the inside of the body

Superficial

closer to the surface

Flexion

decreasing the angle between 2 segments of the body

Extension

increasing the angle between 2 body segments

Abduction

moving away from the midline

Adduction

moving towards the midline

Supination

rotating your palm from facing down to facing up

Pronation

rotating your palm from facing up to facing down

Circumduction

moving in a circle

Inversion

moving the sole of your foot towards the midline

Eversion

moving the sole of your foot away from the midline

Plantarflexion

pointing your toes towards the ground

Dorsiflexion

pointing your toes towards the sky

vertebrae order

7 cervical --> 12 thoracic --> 5 lumbar --> 5 sacral --> 3-4 fused coccygeal

what are true intrinsic back muscles dervied from?

epaxial dermomyotomes

what are extrinisic back muscles derived from?

hypaxial dermomyotome

erector spinae

fourth layer of back muscles made up of spinalis, longissumus, and iliocostalis

erector spinae function

extend the back when bilaterally activated and laterally flex the back ipsilaterally when unilaterally activated

Transverso-spinalis

fifth layer of the back muscles that include rotatores brevis, rotatores longus, mutifidus, and semispinalis

transverso spinalis origin, insertion, and function

origin: transverse processesinsertion: spinous processes varying numbers of higher than originfunction: rotate the vertebral column to rotate the anterior side of the body towards the contralateral side (side opposite the muscle)

whare are ribs derived from?

splaratomes

visceral pleura

membrane adhered to the lungs

parietal pleura

membrane fused to the thoracic cavity

scalenas anterior function

rotates sternum out to increase volume in the thoracic cavity, decreases pressure, and cause deeper breathing

what movements do the anterior-posterior axis allow?

adduction and abduction

what movements do the mediolateral axis allow?

flexion and extension

what movements does th inferior-superior axis allow?

medial-lateral rotation

muscle contraction

force pulls isnertion attachment closer to the fixed origin

Plane joint

bones can only move within that plane (sliding or gliding)

Hinge joint

bones rotate around an axis (flexion and extension only)

Saddle joint

allows sliding but not rotating

Ball and socket

movement along several axes

Condyloid joint

movement in one linear direction and partial movement in a new direction

Pivot joint

rotation

days 0-3

the zona pellucida becomes impermeable to sperm and a rigid barrier forcing volume to remain the same as the cells divide

why does the zona pellucida harden and not allow cells to grow?

This limits the size of the egg as it passes through the fallopian tube to prevent ectopic pregnancy

Day 8

the epiblast, amnion, hypoblast, and primary yolk sac have formed from the embryoblast and hypoblast to create a bilaminar embryo

Day 13

formation of the prochordial plate at the head of the embryo

Day 15

formation of the primitive streak and the cloacal membrane at the tail of the embryo

Day 17

the hypoblast and epiblast become the endoderm and the ectoderm respectively; Mesenchymal cells secreted by the epiblast become the intraembryonic mesoderm between the ectoderm and endoderm to create a trilaminar embryo

day 17-21

notochord formation from intraembryonic mesoderm and folding of the epiblast at the prochordal plate to create the neural grooves and neural folds

where do we see remnants of the notochord in adults?

goo between vertebrae

notochord purpose

gives the body rigidity

Day 20-21

neural groove drops down to become the neural tube and neural folds drop down to become neural crests and edges combine to become surface ectoderm

Day 19-21

intraembryonic mesoderm becomes paraxial mesoderm (somites), intermediate mesoderm, and lateral plate mesoderm

what do somites form?

body segments

Week 4

embryo folds over itself transversely and cranial to caudal finishing key development of the body plan

Day 22

surface ectoderm and lateral plate mesoderm combine to create the somatopleure and endoderm and lateral plate mesoderm combine to create splanchnopleure

Day 28

endoderm folds inwards on itself to create primitive gut tube; intraembryonic coelom folds inwards on itself to create the dorsal mesentery behind the primitive gut tube and the ventral mesentery in front of the primitive gut tube; intraembryonic coelom become pleuroperitoneal cavity

ventral and dorsal mesentery purpose

limit twisting of the gut

what are the ventral and dorsal mesentery derived from?

lateral mesoderm (splanchonopleure)

Day 26

prochordal plate folds 180 degrees to become the oropharyngeal membrane and mesoderm surrounding heart becomes the septum transversum which becomes the diaphragm

Post Day 28

somites divide into dermomyotomes and sclerotomes

dermomyotomes

distal portion of the somites that become the dermis and skeletal muscles

sclerotomes

proximal portion of the somites that become the bones

What do dermomyotomes give rise to?

hypaxial and epaxial dermomyotomes

hypaxial dermomyotome

distal portion of the dermomyotomes that become ventral and lateral dermis and skeletal muscles

epaxial dermomytomes

proximal portion of dermomyotomes that become dorsal dermis and skeletal muscles

What do sclerotomes form?

crnial sclerotomes speaprate and move cranially to fuse with caudal sclerotomes of the sclerotome above it to create vertebrae

what body parts are segmental?

dermomyotomes are segmental

what body parts are intersegmental?

vertebrae

cervical body segments, spinal nerves, and vertebrae

8 cervical segments, 8 cervical spinal nerves, and 7 cervical vertebrae

thoracici body segments, spinal nerves, and vertebrae

12 thoracic segments, 12 thoracic spinal nerves, and 12 thoracic vertebrae

lumbar body segments, spinal nerves, and vertebrae

5 lumbar segments, 5 lumbar spinal nerves, 5 lumbar vertebrae

sacral body segments, spinal nerves, and vertebrae

5 sacral segments, 5 sacral spinal nerves, 5 sacral vertebrae

coccygeal body segments, spinal nerves, and vertebrae

3-4 coccygeal segments, 3-4 coccygeal spinal nerves, and 3-4 coccygeal vertebrae

what are ganglia outside the spinal cord derived from?

neural crest

what are ganglia inside the spinal cord derived from?

neural tube

what kind o innervation only uses the ventral root?

motor innervation

what kind of innervation only uses the dorsal root?

sensory innervation

what kind of structures does somatic motor innervation innervate?

structures derived from somites

somatic motor innervation

Somatic motor axons run from the somatic motor cell bodies in the ventral horn of the spinal gray through the ventral root, intervertebral foramen, spinal nerve, and ventral or dorsal ramus to go to the hypaxial or epaxial dermomyotome respectively

somatic sensory innervation

Information runs from the peripheral processes through the ventral or dorsal ramus, from the hypaxial or epaxial dermomyotomes respectively, through the intervertebral foramen and spinal nerve to the dorsal root ganglion outside the spinal cord, then through the dorsal root to the somatic sensory cell bodies in the dorsal horn of the spinal gray via the central processes

parasympathetic innervation of the midgut and above

Preganglionic parasympathetic axons run from the cell bodies in the brain via the vagus nerve to synapse on the organ walls

parasympathetic innervation of hindgut and pelvis

preganglionic parasympathetic axons run from preganglionic parasympathetic cell bodies in the intermediolateral horn of the spinal gray in S3 and S4 through the ventral root, intervertebral foramen, and spinal to synapse on hindgut and pelvic organs through pelvic splanchnic nerves